典型工况下旋转爆震发动机进气道流动特性研究

Flow Characteristics of Rotating Detonation Engine Inlet under Typical Operating Condition

关键词:  超声速进气道  旋转爆震  运动激波  激波-边界层干扰  数值仿真

Key words:  Supersonic inlet  Rotating detonation  Moving shock  Shock-boundary layer interactions  Numerical simulation

摘要:

为了分析旋转爆震发动机燃烧室高频超高压周向压力脉动对进气道扩张段流动特征的影响，采用三维定常/非定常数值仿真方法对旋转爆震发动机进气道扩张段流动特性开展研究。研究结果表明：受下游燃烧室旋转爆震波影响，扩张段内存在呈螺旋状向上游传播的运动激波；运动激波向上游传播过程中强度衰减、传播速度下降，激波形态由类正激波向类斜激波演化，运动激波逐步向驻激波演变，运动激波/边界层干扰诱发的回流区逐步向波前扩展，波面坐标系下波前亚声区相对厚度逐渐增大；与定常反压状态相比，旋转爆震工作状态进气道出口静温、总温较高，总压较低。

Abstract:

Rotating detonation engine is a new type of propulsion system with great potential. In order to analyze the effects of high frequency and ultra-high pressure circumferential pressure pulsation in the combustor on the flow characteristics of the inlet diffuser， the three-dimensional steady/unsteady numerical simulation method is used to study the flow characteristics of the inlet diffuser of the rotating detonation engine. The results show that under the influence of rotating detonation wave in the downstream combustor， there is a spiral moving shock propagating upstream in the diffuser. With the moving shock propagating upstream， its intensity and propagation velocity decrease， and the shock shape evolves from normal shock to oblique shock with the moving shock evolving into standing shock gradually. The flow separation zone induced by moving shock/boundary layer interaction gradually extends to the wave front and the relative thickness of the subsonic region before moving shock increases gradually in the relative coordinate system with the moving shock propagating upstream. Compared with steady condition，the total temperature and static temperature are higher and the total pressure is lower at the outlet under rotating detonation condition.